June 7 (Bloomberg) -- General Motors Co.’s changes to the
battery of the Chevrolet Volt will extend the 2013 model’s range
beyond Toyota Motor Corp.’s plug-in Prius in miles-per-gallon
equivalent.

GM said the all-electric range of the 2013 Chevrolet Volt
will be 38 miles (61 kilometers) on a single charge after the
company increased battery storage capacity and changed the
cell’s chemistry. That’s an increase of three miles. The model’s
mpg-equivalent will rise to 98 miles from 94, the company said
in a statement on its website.

Toyota’s plug-in Prius gets a 95 mpg-equivalent and the
company has said it’s capable of traveling 15 miles on
electricity alone. GM overtook Toyota in global sales last year
to become the top-selling automaker. The Detroit-based automaker
promotes Volt as an example of the company’s technology and fuel
efficiency.

“I always like it when our numbers are bigger -- when
bigger is better,” Andrew Farah, Volt chief engineer, told
reporters today on a conference call.

The 2013 Volt goes on sale in August and its starting price
will be the same as the 2012 version, Farah said. The 2012 Volt
starts at $39,145, according to GM’s website, before a $7,500
U.S. tax credit.

New ‘Recipe’

For the Volt’s batteries, “the best way to explain what
we’ve done at the cell level is to compare it to a cake batter
recipe,” Bill Wallace, GM director of global battery systems
engineering, said in the statement. “Sometimes if you use more
sugar and less vanilla you get a better tasting cake. We’ve done
some work at the cell level to modify the ‘ingredients’ to make
a better end result.”

Volt was the best-selling rechargeable auto in the U.S.
last month, with deliveries more than tripling to 1,680 from a
year earlier. That topped Prius and Nissan Motor Co.’s all-electric Leaf.

Prius jumped to the world’s third best-selling car line in
the first quarter. U.S. demand and incentives in Japan caused
Prius sales to more than double to 247,230, trailing only
Toyota’s Corolla at 300,800 and 277,000 for Ford Motor Co.’s
Focus.

GM gained 0.1 percent to $21.85 at the close in New York.
The shares have risen 7.8 percent this year.